[Bleeding] Made ItemStack constructors not default to an amount of 0. Fixes BUKKIT-610

By: Celtic Minstrel <celtic.minstrel.ca@some.place>

paper-api/src/main/java/org/bukkit/inventory/ItemStack.java

@@ -20,11 +20,11 @@ public class ItemStack implements Cloneable, ConfigurationSerializable {
     private Map<Enchantment, Integer> enchantments = new HashMap<Enchantment, Integer>();
 
     public ItemStack(final int type) {
-        this(type, 0);
+        this(type, 1);
     }
 
     public ItemStack(final Material type) {
-        this(type, 0);
+        this(type, 1);
     }
 
     public ItemStack(final int type, final int amount) {